Depth-Image-Based Rendering (DIBR) is a technology related to three dimensional video systems. In free viewpoint television (or three-dimensional (3D) video), DIBR is used to generate virtual views based on image and associated depth information. Images used to generate virtual views is called reference views.
DIBR may result in accumulation of noise in the rendered image. During DIBR synthesis, noise present in reference views is projected into the output image. Since the noise of the reference images is not correlated, its presence in different reference views sums up in the rendered output, which increases the noise level of the output image.
Prior art discloses a technique of transmitting multiview images, where noise has been removed. A U.S. Pat. No. 8,643,701 discloses applying first and second depth enhancement before and during view synthesis, to correct errors or suppress noise due to the estimation or acquisition of the dense depth images and sparse depth features. Nevertheless, enhancements before and during view synthesis to correct errors or suppress noise, do not result in the output noise levels, in the output rendered view, being substantially similar to the noise level present in the source, reference image(s).
There is a need to provide an improved method and apparatus for depth-image-based rendering, aiming to improve management of noise present in the base stereo images.